| Title |
Phosphorus discharge from carp culture as a function of phosphorus content in feeds |
| Authors |
김범철 ; 허우명 ; 전만식 ; 김징호 ( Bom Chul Kim ; Woo Myung Heo ; Man Sik Jun ; Jing Ho Kim ) |
| Abstract |
The amount of phosphorus discharge per ㎏ feed from the aquaculture of Israeli carp (Cyprinus carpio) was determined by monitoring the phosphorus discharge in the effluent of culture tanks. 10 commercial fishfeeds were used in order to delineate the relationship between discharge rate of phosphorus from fish culture and the phosphorus content of feeds ranging from 1.0% to 2.1%. 52% of phosphorus in the ingested feed was released into water through excretion. 68% of excreted phosphorus was in particulate form and 32% was in dissolved form. Phosphorus discharge was higher for feeds of higher P-content and also increased with the feed conversion ratio. Higher phosphorus discharge for feeds of higher P-content was mostly contributed by the increase of particulate phosphorus excretion showing positive correlation, whereas dissolved P excretions were at the similar level regardless of P- content. The total phosphorus discharge rate was 8.4(gP/㎏ feed) when the P-content of feed was 1.5%. The discharge rate will be smaller, if the P-content of feeds and the feed conversion ratio are lowered. |